slru-infrastructure

Tune PostgreSQL SLRU buffers by configuring per-consumer GUC parameters to diagnose cache pressure and bank-lock contention. This optimization ensures high-performance transaction tracking and metadata caching for heavy workloads.

The PostgreSQL SLRU subsystem is a Simple LRU mechanism used for critical transaction tracking and metadata caching. It manages core machinery including CLOG, MultiXact, Subtrans, CommitTs, and Notify components to maintain high-performance database operations.

Implementing a new PostgreSQL SLRU consumer requires defining PagePrecedes logic and ensuring correct WAL and crash-recovery behavior. The development process leverages the bank-locked LRU design and on-disk segment management specific to PG 17+.

PostgreSQL SLRU bank-lock contention happens due to high concurrency pressure on shared cache buffers. Resolve it by analyzing the current SLRU buffer configuration and adjusting per-consumer GUC settings to optimize the distribution of locks across the subsystem.

Yes, PostgreSQL 17 introduces per-consumer GUC configuration for SLRU, allowing granular tuning of the Simple LRU subsystem. This enables developers and database administrators to independently manage buffer sizes and resolve wraparound pressure for specific consumers.

You need to manage PostgreSQL SLRU on-disk segment files when developing new SLRU consumers or experiencing wraparound pressure. Proper segment management ensures correct WAL logging and crash-recovery behavior for transaction tracking components like CLOG and MultiXact.